[Understanding DIDs in Greater Depth] Missing annotation in the draft DID ABNF

[mwherman2000]

@talltree In Appendix A of https://github.com/WebOfTrustInfo/rwot8-barcelona/blob/master/draft-documents/understanding-dids-in-greater-depth.md#appendix-a-anbf-for-dids-and-did-urls , there is some sort of "syntax" tag that is missing from the beginning of the draft ABNF specification (to make it machine processable/validateable). See the first (light gray) line in the following:

; !syntax("abnf")
did                       = "did:" method ":" method-specific-idstring
method                    = 1*methodchar
methodchar                = %x61-7A / DIGIT
method-specific-idstring  = idstring *( ":" idstring )
idstring                  = 1*idchar
idchar                    = ALPHA / DIGIT / "." / "-"
did-url                   = did [ did-relative-ref ]
did-relative-ref          = did-fragment-ref / did-content-ref / did-service-ref
did-fragment-ref          = "#" fragment
did-content-ref           = "!" content-id                                                  
content-id                = content-idstring *( ":" content-idstring )                      
content-idstring          = 1*uri-safe-char                                                 
uri-safe-char             = idchar / "_" / pct-encoded
did-service-ref           = "$" service-id [ path-abempty ] [ "?" query ] [ "#" fragment ]
service-id                = service-idstring *( ":" service-idstring )
service-idstring          = 1*uri-safe-char
did-reference             = did-url / did-relative-ref

Here's an example: http://arran.fi.muni.cz/bnfparser2/share/rfc4234-B.1.abnf

[mwherman2000]

Closed with PR https://github.com/WebOfTrustInfo/rwot8-barcelona/pull/161